Use 'global_async_parallel_for' to speed up bfs verify.
Use 'global_async_parallel_for' to speed up bfs verify.

alexfrolov/grappa,uwsampa/grappa,alexfrolov/grappa,alexfrolov/grappa,uwsampa/grappa,uwsampa/grappa,buaasun/grappa,alexfrolov/grappa,buaasun/grappa,buaasun/grappa,uwsampa/grappa,uwsampa/grappa,uwsampa/grappa,buaasun/grappa,alexfrolov/grappa,alexfrolov/grappa,buaasun/grappa,alexfrolov/grappa,uwsampa/grappa,buaasun/grappa,buaasun/grappa